If you are talking about ceiling joists below an otherwise vented attic, then just lay the batts in there and don't worry about height of the joist being a little different. For more than R-19, then lay another layer of some R-11 or R-19 batts perpendicular to the joists, side by side, and on top of the other insulation.
Just be sure to trim it at an angle at the eaves so you leave an air gap for any soffit vents. It shouldn't be high enough to affect any gable vents.
If you have cathedral ceilings, they make a plastic air gap material to staple in the upper joist space next to the roof sheeting to make sure air will flow from the soffit vents to the peak of the roof.
I am not sure of your question and your particular situation, so post back if this didn't answer it. I am also trying to watch the superbowl and type at the same time.
By the way, always put at least 5/8" thick drywall on a ceiling to avoid future problems. Good luck.